How do animals move

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Across
  1. 3. grip or hold, like the tyres on a slippery road
  2. 4. how something is built or put together
  3. 6. the way an animal moves
  4. 7. the act of moving forward of pushing ahead
Down
  1. 1. c change to help survive or do better
  2. 2. the job or purpose of something
  3. 5. how steady or balanced something is